There are two classes of adverbs in Finnish: (1) Independent adverbs, (2)
Adverbial suffixes.
The independent adverbs are often cases of nouns which differ from
postpositions only in this, that they are used absolutely, and not in
connection with another word. Thus in =käydä kaupungin ympäri=, _to go
round the town_, =ympäri= may be described as a postposition, while in
=käydä ympäri=, where it stands alone and absolute, it is an adverb.
Similarly in =kulkea puutarhan ohitse=, _to pass by the garden_,
=ohitse= is a postposition, but in =pian se menee ohitse=, _it will soon
be over_, it is an adverb.